"The fact is Cruise is a great Jack Reacher. He really nails it... There are no subtle camera angles to make him look bigger... No concession to anything at all and it totally works. When people see this movie they're going to agree and then ask themselves, 'What was I making such a big fuss about for a year and a half?'"

And irate fans have been making a fuss ever since learning Cruise would star in Jack Reacher, opening in December. Some have launched protest pages on Facebook. Others have lashed out at Child himself.

"I was aware that it was going to be controversial," the author tells QMI Agency. "But I was happy that it was... The fact that people have an opinion means success."

"It did go way overboard and I think for Tom Cruise himself it must have been a little bit upsetting. Especially since people were criticizing him without having seen the movie."

Child's 17 Jack Reacher titles have sold more than 60 million copies and attracted such fans as Bill Clinton and former St. Louis Cardinals coach Tony La Russa.

Since his beginning in 1997's Killing Floor to the newly-released A Wanted Man, Reacher is a vigilante who dishes out his own brand of justice.

"Fans like that he's the type of character who will do the right thing, whatever the cost," Child says. "His [usually violent] sense of justice and his unwillingness to compromise is very attractive to people."

We get some sense of that from the trailer for Jack Reacher, which adapts Child's ninth Reacher novel, One Shot. But still, clean-cut Cruise doesn't exactly channel the "big, ugly, bruiser" from the book's pages.

"Whoever the actor was that played Reacher, it would have been purely coincidental if they matched him physically," Child says. "I knew from the start that Cruise might well play the part and I hoped that he would because he's a terrific character actor.

“The fact is Cruise is a great Jack Reacher. He really nails it... There are no subtle camera angles to make him look bigger... no concession to anything at all and it totally works. When people see this movie they’re going to agree and then ask themselves, ‘What was I making such a big fuss about for a year and a half?’”